I recently bought a 93 GMC 3/4 ton 4x4 with a blown 350. I swsapped a 97 Vortec into it, mainly because I already had the engine (used with 70k miles). My brother gave me an LT4 (not LT4 Hot, just LT4) cam that he bought for his 94 Impala SS but never installed. I installed this cam along with Comp Cams beehive springs, Crane 1.6 roller rockers, Crusader TBI to Vortec intake, custom chip, headers, bored TBI, etc.

Long story short, I spun three of five main bearings plling my travel trailer (only a 21 footer). I think I over revved it, as it didnt make mch power.

I now have a rebuilt 350 Vortec short block to put in it, and have to decide about going with the LT4 Cam, stock Vortec cam (L31?) or aftermarket... I ned a torque cam. THe LT4 cam didnt seem to have much torque, but I never drove the truck with the stock 350 TBI, so I have no bass for comparison...

Brian at TBIchips.com that sold me the custon chip said that the LT4 cam was the best torque cam ...???

I don't remember the specs on the LT4 cam, but I really like the cam that GM used in the Ram Jet 350 and the HT383. It's the same cam but in the Ram Jet they used 1.6 rockers. I've had experience with this cam in a 355, flat tops, Vortec heads and 1.5 rockers and IMO it had good low to mid range torque. You can often times pick up this cam on ebay as new take outs for ~$80. I don't remember the entire part number for the cam but the last 4 digits are 7395

LT4 (12551142) cam specs are .476/.480 w/1.6 rockers, 203/210 duration and 115 LCA. I would not consider that a "torque" cam.

Part Number for the cam referenced above is "14097395" - .431/.451 lift w/1.5 rockers, 196/206 duration and 109 LCA.

That's kinda what I thought... I wanted to et some more input before sticking the LT4 cam into this rebuilt short block that I am putting in this weekend. I should have trusted my instinct that anything originally made for a Corvette wasn't right for a big 4x4 truck...I will look into another cam. Anyone looking for an LT4 cam with around 1k miles on it?

I get what I think is conflicting info. The '98 engine originally had an auto trans attached. When I swapped it, into the '93, I had the 93 flywheel resurfaced, installed a thrust bushin in the crank and installed all of it with a new clutch, throwout bearing and pressure plate for a 93 truck, since it still has the 93 NV4500 5 speed trans. it all seemed to work OK, and I never noticed any vibration or anything...When I got to the Autozone site and look up a flywheel for a 98 K2500 manual trans flywheel and a 93 K2500 manual trans flywheel, they are the same part #. When i go t O'Reilly's, I get two choices for each year, one of the two choices is the same part number for both, the other is not. The 98 listing mentions a NV3500, the 93 doesn't. They show to have both part numbers in stock, so I plan to call them to make sure they do and go take a look when they open. My brother is bringing the rebuilt short block and I am going to try and get it set in the truck while I have help.

After some checking, I pulled the trigger on the Comp Cams X4258HR. Got it at Summit for $265. (Still an Ouch) At least I get 90 days no interest to pay for it on the Summit Speed card. Thanks to everyone for the advice. I saved a little by checking out my current roller lifters and plan to reuse them. I already have Comp Cams "beehive" springs in the vortec heads.

After some checking, I pulled the trigger on the Comp Cams X4258HR. Got it at Summit for $265. (Still an Ouch) At least I get 90 days no interest to pay for it on the Summit Speed card. Thanks to everyone for the advice. I saved a little by checking out my current roller lifters and plan to reuse them. I already have Comp Cams "beehive" springs in the vortec heads.

Cool; let us know how it goes! I've installed a few of these in otherwise stock trucks and the owners have been very happy. I'm 100% sure you'll like it better than the LT4 cam!

I believe that WIDESIDE72 bought the X4258HR pn. 08-409-8 which has different specs than the XR258HR pn. 08-408-8. I mention this since the different cam will net different max valve lift with the 1.6 rockers. This may be a factor when checking spring and retainer clearences.

After some checking, I pulled the trigger on the Comp Cams X4258HR. Got it at Summit for $265. (Still an Ouch) At least I get 90 days no interest to pay for it on the Summit Speed card. Thanks to everyone for the advice. I saved a little by checking out my current roller lifters and plan to reuse them. I already have Comp Cams "beehive" springs in the vortec heads.

I believe that WIDESIDE72 bought the X4258HR pn. 08-409-8 which has different specs than the XR258HR pn. 08-408-8. I mention this since the different cam will net different max valve lift with the 1.6 rockers. This may be a factor when checking spring and retainer clearences.

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1972 chevy cheyenne 10,nothing special at the moment,Its a work in progress, Working on the engine, paint and body,engine, paint and body,now its the suspenion, ahh hell I'm about tired of working on it. Maybe it will be a rat rod.

It was an EBAY buy from Mississippi... Originally a a marine app. No EGR. Scored it for $100 (!), I believe about a third of a GMPP intake. I was planning on this swap for a while was watchin feebay for it or comparable. "Even a blind hog can find an acorn once in a while."

Got the Comp Cam from Summit the day before Thanksgiving,but was gone til Sunday after Thanksgiving. I got the cam slipped in, but work has stalled as all I have is a shade tree for cover. It's predicted to snow in Austin area and has been in the 40's all week during the day.

...or to clean out all the junk I have accumulated in my barn. There was ICE outside this AM. It was actually colder last weekend, due to the wind. At least is was still this AM. I had to leave the motor hanging from the A-Frame, as my brother and I ran out of daylight last weekend, as I also had a Ford (Argh)tractor to work on while I had help. I wrapped plastic through the engine tilter/ lifter, then wrapped a tarp around the whole engine. I just had the pan on with a couple of bolts since the cam I bought hadn't come up yet. I pulled it to double check that I had tightend the oil pump bolt, and there was a big chunk of ice around the pump, from rain water that got in! I chipped it off before it occurred to me to take a pic. I got it cleaned up. Luckily since the cam wasn't in yet, the rockers and push rods weren't in either, so no valves were open to let water into the cylinders. My buddy and I got the engine set in and the engine well tarped for the night.